Macbook pro 13'' not charging

Hi everyone, I have a problem on my macbook pro 13'' 2011 early.
Today when charging the amperage be negative. I'm nothing to do any thing that about -200mA when open app up to -2000mA when I charging
while plugged in, the battery charge indicator will begin dropping from 100% what wrong to my macbook.

How to fix it or I should change magsafe from 60w to 85w ?
but I not sure that work.

I try to SMC reset and then not work.

I hope someone to know about that what can I do to make it normal ?
when I run bootcamp with plugged in and run some app, the battery charge indicator will begin dropping. I think it not enougth power from Magsafe 60w or other problem with my macbook pro?

Thank you for your answer, LED on my magsafe when fully charging (100%) is green but when open more application that change to orange with 100% and drain my battery, this is like under heavy load not enough power I'm not sure when charging the normal number of amperage at Power system report
should to be? I'm just 1500mA when charging without application use.

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